Witch

Today is a quadruple-witch day. Quadruple-witching occurs on the 3rd Friday of every last month of the quarter when index futures, index options, stock options and stock futures expire on the same day. Since single stock futures were launched in December 2002 there have been 29 quadruple witches.

Here are the historical averages for the markets and volatility on those days.  More often than not, quad-witching days have been slightly positive for the markets.  They are, however, more volatile.